Player Controller - Pro Unity Game Development with C# - page 156

16 void Awake()
17 {
18 //If mobile platform, then use mobile first person controller
19 #if UNITY_IPHONE || UNITY_ANDROID || UNITY_WP8
20 DesktopFirstPerson.SetActive(false);
21 MobileFirstPerson.SetActive(true);
22 #endif
23 }
24 //------------------------------------------------
25 }
 Lines 09-12. This class defines two public variables: DesktopFirstPerson and
MobileFirstPerson . These are references to each of the controllers, one of
which should be disabled on Awake .
 Lines 19-22. The Awake event is called implicitly before Start , when the scene
begins. Line 19 uses the Platform Dependent Compilation syntax to define two
subsequent lines that should execute, only if the platform is iPhone, Android, or
Windows Phone. The global flag UNITY_IPHONE encompasses all iOS devices,
such as iPads and iPhones. In this sample, if the platform is a mobile device,
then the desktop controller is deactivated and the mobile controller is activated.
Notice there is no branch for a desktop platform. Why? We can simply avoid
coding this branch by deactivating the mobile First Person Controller by default
in the Unity Editor . This way, the default configuration saves us coding and time!
It's important to understand both what is happening and is not happening regarding Platform
Dependent Compilation. Line 19 of Listing 5-1 is not executed every time the game runs on every
platform. The Awake function is not performing a runtime check for the active Unity platform, and
then acting accordingly. The #if directive is not the same as an if statement. The #if directive
works at the compilation level and not at a runtime level. In practice, Listing 5-1 means that when the
Unity platform is switched to desktop, the compiler recompiles the ControlSwitcher script and treats
lines 19-22 as code comments , since the active platform is not a mobile one. The compiler only
recognizes lines 19-22 as valid when the active platform is mobile.
Go ahead and give this code a try—the result is a universal First Person Controller. Whether you're
on desktop or mobile, your scene now has a First Person Controller ready to use!
Note If you just want to make a runtime check for the active Unity platform, then use Application.
platform . See the online Unity documentation at https://docs.unity3d.com/Documentation/
ScriptReference/Application-platform.html .
Head Bobbing and Sine Waves
Whenever the First Person Controller walks forward or backward, we want the camera to bob or
oscillate up and down smoothly in the Y axis. This is to simulate the involuntary head movement that
occurs naturally whenever most bipeds, like humans, move using their legs. We could, of course,
implement this behavior by resorting to the familiar bobbing motion technique created for the Cash
Power-Up in the previous chapter. But this motion was decidedly linear and mechanical . That is,